Nonvolatle memory device and memory system having the same, and related memory management, erase and programming methods

Patent metadata

Field	Value
Publication number	US-9818485-B2
Application number	US-201615178135-A
Country	US
Kind code	B2
Filing date	Jun 9, 2016
Priority date	Jul 11, 2012
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

An erase method of a nonvolatile memory device includes setting an erase mode, and performing one of a normal erase operation and a quick erase operation according to the set erase mode. The normal erase operation is performed to set a threshold voltage of a memory cell to an erase state which is lower than a first erase verification level. The quick erase operation is performed to set a threshold voltage of a memory cell to a pseudo erase state which is lower than a second erase verification level. The second erase verification level is higher than the first erase verification level.

First claim

What is claimed is:

1. A program method of a memory system which comprises a nonvolatile memory device including a plurality of memory blocks and a memory controller to control the nonvolatile memory device, the program method comprising:
receiving data and an address corresponding to a memory block from among the plurality of memory blocks;
determining whether an erase operation is needed on the memory block;
determining whether a quick erase operation is needed, when the erase operation is needed;
performing the quick erase operation on the memory block to form a pseudo erase state when the quick erase operation is needed;
performing a normal erase operation on the memory block to form an erase state when the quick erase operation is not needed; and
programming the memory block with the input data after said performing the quick erase operation and after said performing the normal erase operation,
wherein the erase state is lower than a first erase verification level, the pseudo erase state is lower than a second erase verification level, and the second erase verification level is higher than the first erase verification level,
wherein the quick erase operation is selected based on a success rate of erase operations, program operations, or read operations of the memory block.

2. The program method of claim 1 , wherein the erase operation is determined as needed when the memory block has invalid data or garbage after a merge operation between the plurality of memory blocks and a free block is needed.

3. The program method of claim 1 , wherein said programming is an M-bit program operation (M being a natural number) of the memory block using the erase state.

4. The program method of claim 1 , wherein said programming is an N-bit program operation (N being a positive integer) of the memory block using the pseudo erase state.

5. The program method of claim 4 , wherein during the N-bit program operation a threshold voltage of the pseudo erase state is higher than a threshold voltage of the erase state.

6. The program method of claim 4 , wherein the N-bit program operation uses an extra state higher than a most significant state of an M-bit program operation (M being a natural number) using the erase state.

7. The program method of claim 4 , wherein the N-bit program operation is a multi-dimension modulation scheme in which data to be stored is encoded and the encoded data is continuously programmed in memory cells of the memory block.

8. The program method of claim 1 , wherein the memory block includes a three-dimensional (3D) array of memory cells.

9. The program method of claim 1 , wherein the quick erase operation is selected when the success rate of erase operations, program operations, or read operations of the memory block is less than a predetermined value.

10. The program method of claim 1 , wherein the quick erase operation is selected when the success rate of erase operations, program operations, or read operations of the memory block exceeds a predetermined value.

11. A memory system, comprising:
at least ne nonvolatile memory device; and
a memory controller configured to control the at least one nonvolatile memory device,
wherein the at least one nonvolatile memory device comprises
a first memory cell array including first memory blocks each having a plurality of first memory cells at which page data is stored by 1-bit programming,
a second memory cell array including second memory blocks each having a plurality of second memory cells, a plurality of page data in the first memory cell array being stored at a page of the second memory cells by multi-bit programming, and
control logic configured to erase the first memory blocks using one of a first erase mode and a second erase mode, and to erase the second memory blocks using the first erase mode,
wherein the first erase mode is used to set the first memory cells or the second memory cells to an erase state, and the second erase mode is used to set the first memory cells to a pseudo erase state,
wherein the erase state is lower than a first erase verification level, the pseudo erase state is lower than a second erase verification level, and the second erase verification level is higher than the first erase verification level, and
wherein the second erase mode is selected based on a success rate of erase operations, program operations, or read operations of the first memory blocks.

12. The memory system of claim 11 , wherein each of the first memory blocks in the first memory cell array performs a 1-bit program operation using the erase state and then performs a 1-bit program operation using the pseudo erase state.

13. The memory system of claim 11 , wherein the second erase mode is selected when the success rate of erase operations, program operations, or read operations of the first memory blocks is less than a predetermined value.

14. The memory system of claim 11 , wherein the second erase mode is selected when the success rate of erase operations, program operations, or read operations of the first memory blocks exceeds a predetermined value.

15. The memory system of claim 11 , wherein the memory controller comprises an error correction code circuit configured to correct an error of a plurality of pages of data read from the first memory cell array when the plurality of pages of data of the first memory cell array is multi-bit programmed for the page.

16. The memory system of claim 11 , wherein the second erase mode applies an erase voltage which is lower than a level of an erase voltage of the first erase mode, and performs a part of erase cycles of the first erase mode, a part of one of the erase cycles of the first erase mode, erase cycles which are shorter than the erase cycles of the first erase mode, a part of the erase cycles which are shorter than the erase cycles of the first erase mode, or a part of one of the erase cycles which are shorter than the erase cycles of the first erase mode.

17. The memory system of claim 11 , wherein at least one of the first and second memory cell arrays is a three-dimensional (3D) memory cell array.

18. The memory system of claim 17 , wherein the 3D memory cell array comprises a plurality of memory cells, each of the memory cells including a charge trap layer.

19. The memory system of claim 17 , wherein the 3D memory cell array includes a plurality of pillars penetrating at least one ground selection line, a plurality of word lines, and the at least one string selection line.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Oh Eun Chu
• Kim Jongha
• Kong Junjin

Classifications

• G11C16/0466

  comprising cells with charge storage in an insulating layer, e.g. metal-nitride-oxide-silicon [MNOS], silicon-oxide-nitride-oxide-silicon [SONOS] (G11C16/0483, G11C16/0491 take precedence) · CPC title

• G06F12/0246

  in block erasable memory, e.g. flash memory · CPC title

• G06F2212/7205

  Cleaning, compaction, garbage collection, erase control · CPC title

• G11C16/0416 Primary

  comprising cells containing a single floating gate transistor and no select transistor, e.g. UV EPROM · CPC title

• G06F12/0253

  Garbage collection, i.e. reclamation of unreferenced memory · CPC title